Mitigation of pattern sensitivity in full-field electronic dispersion compensation

We investigate the pattern-dependent decoding failures in full-field electronic dispersion compensation (EDC) by offline processing of experimental signals, and find that the performance of such an EDC receiver may be degraded by an isolated "1" bit surrounded by long strings of consecutive "0s". By reducing the probability of occurrence of this kind of isolated "1" and using a novel adaptive threshold decoding method, we greatly improve the compensation performance to achieve 10-Gb/s on-off keyed signal transmission over 496-km field-installed single-mode fiber without optical dispersion compensation.

Labeled EF-Tus for rapid kinetic studies of pretranslocation complex formation

The universally conserved translation elongation factor EF-Tu delivers aminoacyl(aa)-tRNA in the form of an aa-tRNA·EF-Tu·GTP ternary complex (TC) to the ribosome where it binds to the cognate mRNA codon within the ribosomal A-site, leading to formation of a pretranslocation (PRE) complex. Here we describe preparation of QSY9 and Cy5 derivatives of the variant E348C-EF-Tu that are functional in translation elongation. Together with fluorophore derivatives of aa-tRNA and of ribosomal protein L11, located within the GTPase associated center (GAC), these labeled EF-Tus allow development of two new FRET assays that permit the dynamics of distance changes between EF-Tu and both L11 (Tu-L11 assay) and aa-tRNA (Tu-tRNA assay) to be determined during the decoding process. We use these assays to examine: (i) the relative rates of EF-Tu movement away from the GAC and from aa-tRNA during decoding, (ii) the effects of the misreading-inducing antibiotics streptomycin and paromomycin on tRNA selection at the A-site, and (iii) how strengthening the binding of aa-tRNA to EF-Tu affects the rate of EF-Tu movement away from L11 on the ribosome. These FRET assays have the potential to be adapted for high throughput screening of ribosomal antibiotics.

'It’d be useful, but I wouldn’t use it':barriers to university students’ feedback seeking and recipience

For feedback to be effective, it must be used by the receiver. Prior research has outlined numerous reasons why students’ use of feedback is sometimes limited, but there has been little systematic exploration of these barriers. In 11 activity-oriented focus groups, 31 undergraduate Psychology students discussed how they use assessment feedback. The data revealed many barriers that inhibit use of feedback, ranging from students’ difficulties with decoding terminology, to their unwillingness to expend effort. Thematic analysis identified four underlying psychological processes: awareness, cognisance, agency, and volition. We argue that these processes should be considered when designing interventions to encourage students’ engagement with feedback. Whereas the barriers identified could all in principle be removed, we propose that doing so would typically require – or would at least benefit from – a sharing of responsibility between teacher and student. The data highlight the importance of training students to be proactive receivers of feedback.

Concurrent codes:a holographic-type encoding robust against noise and loss

Concurrent coding is an encoding scheme with 'holographic' type properties that are shown here to be robust against a significant amount of noise and signal loss. This single encoding scheme is able to correct for random errors and burst errors simultaneously, but does not rely on cyclic codes. A simple and practical scheme has been tested that displays perfect decoding when the signal to noise ratio is of order -18dB. The same scheme also displays perfect reconstruction when a contiguous block of 40% of the transmission is missing. In addition this scheme is 50% more efficient in terms of transmitted power requirements than equivalent cyclic codes. A simple model is presented that describes the process of decoding and can determine the computational load that would be expected, as well as describing the critical levels of noise and missing data at which false messages begin to be generated.

Duppying yoots in a dog eat dog world, kmt:determining the senses of slang terms for the Courts

I describe and discuss a series of court cases which focus upon on decoding the meaning of slang terms. Examples include sexual slang used in a description by a child and an Internet Relay Chat containing a conspiracy to murder. I consider the task presented by these cases for the forensic linguist and the roles the linguist may assume in determining the meaning of slang terms for the Courts. These roles are identified as linguist as naïve interpreter, lexicographer, case researcher and cultural mediator. Each of these roles is suggestive of different strategies that might be used from consulting formal slang dictionaries and less formal Internet sources, to collecting case specific corpora and examining all the extraneous material in a particular case. Each strategy is evaluated both in terms of the strength of evidence provided and its applicability to the forensic context.

Costs and benefits of orthographic inconsistency in reading:evidence from a cross-linguistic comparison

We compared reading acquisition in English and Italian children up to late primary school analyzing RTs and errors as a function of various psycholinguistic variables and changes due to experience. Our results show that reading becomes progressively more reliant on larger processing units with age, but that this is modulated by consistency of the language. In English, an inconsistent orthography, reliance on larger units occurs earlier on and it is demonstrated by faster RTs, a stronger effect of lexical variables and lack of length effect (by fifth grade). However, not all English children are able to master this mode of processing yielding larger inter-individual variability. In Italian, a consistent orthography, reliance on larger units occurs later and it is less pronounced. This is demonstrated by larger length effects which remain significant even in older children and by larger effects of a global factor (related to speed of orthographic decoding) explaining changes of performance across ages. Our results show the importance of considering not only overall performance, but inter-individual variability and variability between conditions when interpreting cross-linguistic differences.

Weakly-constrained codes for suppression of patterning effects in digital communications

We propose weakly-constrained stream and block codes with tunable pattern-dependent statistics and demonstrate that the block code capacity at large block sizes is close to the the prediction obtained from a simple Markov model published earlier. We demonstrate the feasibility of the code by presenting original encoding and decoding algorithms with a complexity log-linear in the block size and with modest table memory requirements. We also show that when such codes are used for mitigation of patterning effects in optical fibre communications, a gain of about 0.5dB is possible under realistic conditions, at the expense of small redundancy 10%). © 2006 IEEE.

Effects of phonetic/phonics instruction on reading pronunciation (French level I)

Pronunciation training has been traditionally viewed as of limited importance in a communicatively oriented foreign language curriculum (Pennington & Richards, 1986). Many language instructors seemingly deny the usefulness of phonetic training and rely on a listen-and-repeat method with the use of audiotapes (Bate, 1989; Callamand & Pedoya, 1984; Jones, 1997). Beginners in French classes face the challenge of mastering a complex sound and grapheme-phoneme correspondence system without the benefit of specific instruction. Their pronunciation errors develop mostly from bad habits while decoding from print to sound (Dansereau, 1995). ^ The purpose of this study was to investigate the effectiveness of basic phonetic/phonics instruction on reading pronunciation accuracy in a French I language course. ^ The sample consisted of two groups of French I students from Florida International University, who received the same instruction in French language and culture during the fall semester of 1999. Only the experimental group received additional phonetic/phonics training. ^ The instrument consisted of three recorded reading tasks: isolated familiar words, isolated unfamiliar words, and dialogue. Research questions were analyzed using a one-way multivariate analysis of variance. Significant differences were found between the two groups on scores for each of the three sections of the instrument, and on the total scores. These findings support the hypothesis of the study and reveal the effectiveness of phonetic/phonics training for beginners of French. ^ The findings imply that beginning language students should receive the minimum knowledge they need to master the French phoneme-grapheme (sound-spelling) system. ^

The effects of using rap music on the fluency skills of 2nd grade African American students

A concern for both educators and policy makers is how to increase the reading achievement of African American students. Studies have shown that rap music, which has its roots in the African American community, can be used as a tool to facilitate this increase, specifically how using rap songs in reading lessons can improve a child's reading motivation, information recall, and vocabulary development. There are also studies on how repeated reading of a text can help improve a child's reading fluency. Yet, there are no studies that combine rap music and repeated reading of a text. This study describes the effects of using a culturally responsive reading strategy on the fluency, decoding, and comprehension skills of African American students. ^ The sample consisted of 105 African American students within eight, second grade classrooms at two different elementary schools. The classes were randomly selected and assigned to the rap group or the control group. Students received eight half-hour sessions using either a rap text or a traditional text in a repeated reading lesson. All of the students were pre-tested and post-tested on the Oral Reading Fluency and the Nonsense Word Fluency portions of the Dynamic Indicators of Basic Literacy Skills Test. Additionally, a researcher constructed comprehension quiz was given to the students at the beginning, middle, and end of the study. Research questions were analyzed using ANOVAs and t tests. ^ The hypotheses were not supported but there was some evidence that rap music in a reading lesson helped improve the fluency skills of African American students at one of the schools. The results also revealed that rap music used in a reading lesson initially improved the comprehension skills of African American students. The rap treatment may not have worked best overall because of the lack of intensity of the treatment. ^ The study has shown some evidence to support using culturally appropriate materials such as rap with students. There needs to be more research on the interaction between teaching methods, materials, and students. ^

Digital surveillance based on video CODEC System-on-a-Chip (SoC) platforms

Today, most conventional surveillance networks are based on analog system, which has a lot of constraints like manpower and high-bandwidth requirements. It becomes the barrier for today's surveillance network development. This dissertation describes a digital surveillance network architecture based on the H.264 coding/decoding (CODEC) System-on-a-Chip (SoC) platform. The proposed digital surveillance network architecture includes three major layers: software layer, hardware layer, and the network layer. The following outlines the contributions to the proposed digital surveillance network architecture. (1) We implement an object recognition system and an object categorization system on the software layer by applying several Digital Image Processing (DIP) algorithms. (2) For better compression ratio and higher video quality transfer, we implement two new modules on the hardware layer of the H.264 CODEC core, i.e., the background elimination module and the Directional Discrete Cosine Transform (DDCT) module. (3) Furthermore, we introduce a Digital Signal Processor (DSP) sub-system on the main bus of H.264 SoC platforms as the major hardware support system for our software architecture. Thus we combine the software and hardware platforms to be an intelligent surveillance node. Lab results show that the proposed surveillance node can dramatically save the network resources like bandwidth and storage capacity.

Space time coding for polynomial phase modulated signals

Polynomial phase modulated (PPM) signals have been shown to provide improved error rate performance with respect to conventional modulation formats under additive white Gaussian noise and fading channels in single-input single-output (SISO) communication systems. In this dissertation, systems with two and four transmit antennas using PPM signals were presented. In both cases we employed full-rate space-time block codes in order to take advantage of the multipath channel. For two transmit antennas, we used the orthogonal space-time block code (OSTBC) proposed by Alamouti and performed symbol-wise decoding by estimating the phase coefficients of the PPM signal using three different methods: maximum-likelihood (ML), sub-optimal ML (S-ML) and the high-order ambiguity function (HAF). In the case of four transmit antennas, we used the full-rate quasi-OSTBC (QOSTBC) proposed by Jafarkhani. However, in order to ensure the best error rate performance, PPM signals were selected such as to maximize the QOSTBC’s minimum coding gain distance (CGD). Since this method does not always provide a unique solution, an additional criterion known as maximum channel interference coefficient (CIC) was proposed. Through Monte Carlo simulations it was shown that by using QOSTBCs along with the properly selected PPM constellations based on the CGD and CIC criteria, full diversity in flat fading channels and thus, low BER at high signal-to-noise ratios (SNR) can be ensured. Lastly, the performance of symbol-wise decoding for QOSTBCs was evaluated. In this case a quasi zero-forcing method was used to decouple the received signal and it was shown that although this technique reduces the decoding complexity of the system, there is a penalty to be paid in terms of error rate performance at high SNRs.

The Effectiveness of Explicit Individualized Phonemic Awareness Instruction By a Speech-Language Pathologist to Preschool Children With Phonological Speech Disorders

This study investigated the effects of an explicit individualized phonemic awareness intervention administered by a speech-language pathologist to 4 prekindergarten children with phonological speech sound disorders. Research has demonstrated that children with moderate-severe expressive phonological disorders are at-risk for poor literacy development because they often concurrently exhibit weaknesses in the development of phonological awareness skills (Rvachew, Ohberg, Grawburg, & Heyding, 2003). The research design chosen for this study was a single subject multiple probe design across subjects. After stable baseline measures, the participants received explicit instruction in each of the three phases separately and sequentially. Dependent measures included same-day tests for Phase I (Phoneme Identity), Phase II (Phoneme Blending), and Phase III (Phoneme Segmentation), and generalization and maintenance tests for all three phases. All 4 participants made substantial progress in all three phases. These skills were maintained during weekly and biweekly maintenance measures. Generalization measures indicated that the participants demonstrated some increases in their mean total number of correct responses in Phase II and Phase III baseline while the participants were in Phase I intervention, and more substantial increases in Phase III baseline while the participants were in Phase II intervention. Increased generalization from Phases II to III could likely be explained due to the response similarities in those two skills (Cooper, Heron, & Heward, 2007). Based upon the findings of this study, speech-language pathologists should evaluate phonological awareness in the children in their caseloads prior to kindergarten entry, and should allocate time during speech therapy to enhance phonological awareness and letter knowledge to support the development of both skills concurrently. Also, classroom teachers should collaborate with speech-language pathologists to identify at-risk students in their classrooms and successfully implement evidence-based phonemic awareness instruction. Future research should repeat this study including larger groups of children, children with combined speech and language delays, children of different ages, and ESOL students

A (não) assunção da responsabilidade enunciativa em livros didáticos de língua portuguesa dos 4º e 5º anos

Portuguese textbook has been the focus of many investigations, nevertheless, the theme still has much to be discussed, reflected and broadened. This conviction mobilized us to perform this research, seeking to answer three questions: (1) how does the author of the textbook induce the student to give his opinion in comprehension questions of text in Portuguese textbook of 4th and 5thgrade? Which enunciative links are used by the author of the textbook in comprehension questions of text concerning to the assumption of enunciative responsability? And (3) Which enunciative links are used by the author of the textbook in comprehension questions of text concerning to the non assumption of enunciative responsability? In this direction, we define as objective to id entify, describe, analyze and interpret how the (non) assumption of enunciative responsibility materializes itself in Portuguese textbooks. The theme is echoed in the guidelines of the Parâmetros Curriculares Nacionais PCN (1998; 2001), who assume that all education committed to citizenship need to create conditions in order the student can develop his discursive competence" (BRAZIL, 1998, p. 23). This assertion of PCN (1998; 2001) is closely related to our research object, and therefore, it has corroborated to the accomplishment of this study. So, we analyze the comprehension questions of the texts that are elaborated by the authors of Portuguese textbooks of the 4th and 5th grade, used at public schools in the city of Natal-RN in 2010. As a theoretical basis, we have considered the postulates of Textual Analysis of Discourses ATD and Enunciative Linguistics. Our research was mainly based on the studies of Adam (2011), Nølke (1994; 2001; 2006; 2009; 2013), Nølke, Fløttum e Norén (2004) Rabatel (2004; 2005; 2008; 2009), Guentchéva (1994; 1996). Our data analysis revealed that the authors of Portuguese textbooks explore the reading comprehension, inducing students to answer questions that may be categorized like: (1) induction to the assumption of enunciative responsibility, (2) induction for non assumption the enunciative responsibility, (3) orientation for the study of vocabulary and grammar and (4) orientation of extra themes. The results from the comparison of the books of 4th and 5th grade of the two analyzed collections, we observed through the links of (non) responsability Nølke (1994; 2001; 2006; 2009; 2013), Nølke, Fløttum e Norén (2004), which in 79% of the questions, the authors induce the decoding of a content objectively inscribed in the text. In this sense, the notion of understanding a text is compromised, since it is limited to copying contents or transcription exercises, failing to consider the interactive use of language, or rather, failing to expand the student's knowledge in the (re)construction of the text of the meanings. This shows that there is a lack in the deal with the text that includes the textual discursive resources in the reading activities in Portuguese textbooks. We recall, in this direction, the works of Marcuschi (2005), Antunes (2003, 2005), and Bunzen Rojo (2008), among others authors who contributed greatly to orient the choice of Portuguese textbooks. Finally, we believe that the study about the enunciative responsibility phenomenon in Portuguese texto oks offers, above all, instruments in order to the interlocutors identify the elements present in the enunciation and the effects that these elements bring to the (re) construction of the meanings in texts that they read and write in the classroom.

Calcium/Calmodulin-Dependent Protein Kinase II Serves as a Biochemical Integrator of Calcium Signals for the Induction of Synaptic Plasticity

Repetitive Ca2+ transients in dendritic spines induce various forms of synaptic plasticity by transmitting information encoded in their frequency and amplitude. CaMKII plays a critical role in decoding these Ca2+ signals to initiate long-lasting synaptic plasticity. However, the properties of CaMKII that mediate Ca2+ decoding in spines remain elusive. Here, I measured CaMKII activity in spines using fast-framing two-photon fluorescence lifetime imaging. Following each repetitive Ca2+ elevations, CaMKII activity increased in a stepwise manner. This signal integration, at the time scale of seconds, critically depended on Thr286 phosphorylation. In the absence of Thr286 phosphorylation, only by increasing the frequency of repetitive Ca2+ elevations could high peak CaMKII activity or plasticity be induced. In addition, I measured the association between CaMKII and Ca2+/CaM during spine plasticity induction. Unlike CaMKII activity, association of Ca2+/CaM to CaMKII plateaued at the first Ca2+ elevation event. This result indicated that integration of Ca2+ signals was initiated by the binding of Ca2+/CaM and amplified by the subsequent increases in Thr286-phosphorylated form of CaMKII. Together, these findings demonstrate that CaMKII functions as a leaky integrator of repetitive Ca2+ signals during the induction of synaptic plasticity, and that Thr286 phosphorylation is critical for defining the frequencies of such integration.

Ribosomal frameshifting and transcriptional slippage: from genetic steganography and cryptography to adventitious use

Genetic decoding is not ‘frozen’ as was earlier thought, but dynamic. One facet of this is frameshifting that often results in synthesis of a C-terminal region encoded by a new frame. Ribosomal frameshifting is utilized for the synthesis of additional products, for regulatory purposes and for translational ‘correction’ of problem or ‘savior’ indels. Utilization for synthesis of additional products occurs prominently in the decoding of mobile chromosomal element and viral genomes. One class of regulatory frameshifting of stable chromosomal genes governs cellular polyamine levels from yeasts to humans. In many cases of productively utilized frameshifting, the proportion of ribosomes that frameshift at a shift-prone site is enhanced by specific nascent peptide or mRNA context features. Such mRNA signals, which can be 5′ or 3′ of the shift site or both, can act by pairing with ribosomal RNA or as stem loops or pseudoknots even with one component being 4 kb 3′ from the shift site. Transcriptional realignment at slippage-prone sequences also generates productively utilized products encoded trans-frame with respect to the genomic sequence. This too can be enhanced by nucleic acid structure. Together with dynamic codon redefinition, frameshifting is one of the forms of recoding that enriches gene expression.